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  • Vista/7: How to get glass color?

    - by Ian Boyd
    How do you use DwmGetColorizationColor? The documentation says it returns two values: a 32-bit 0xAARRGGBB containing the color used for glass composition a boolean parameter that is true "if the color is an opaque blend" (whatever that means) Here's a color that i like, a nice puke green: You can notice the color is greeny, and the translucent title bar (against a white background) shows the snot color very clearly: i try to get the color from Windows: DwmGetColorizationColor(dwCcolorization, bIsOpaqueBlend); And i get dwColorization: 0x0D0A0F04 bIsOpaqueBlend: false According to the documentation this value is of the format AARRGGBB, and so contains: AA: 0x0D (13) RR: 0x0A (10) GG: 0x0F (15) BB: 0x04 (4) This supposedly means that the color is (10, 15, 4), with an opacity of ~5.1%. But if you actually look at this RGB value, it's nowhere near my desired snot green. Here is (10, 15, 4) with zero opacity (the original color), and (10,15,4) with 5% opacity against a white/checkerboard background: So the question is: How to get glass color in Windows Vista/7? i tried using DwmGetColorizationColor, but that doesn't work very well. A person with same problem, but a nicer shiny picture to attract you squirrels: So, it boils down to – DwmGetColorizationColor is completely unusable for applications attempting to apply the current color onto an opaque surface. i love this guy's screenshots much better than mine. Using his screenshots as a template, i made up a few more sparklies: For the last two screenshots, the alpha blended chip is a true partially transparent PNG, blending to your browser's background. Cool! (i'm such a geek) Edit 2: Had to arrange them in rainbow color. (i'm such a geek) Edit 3: Well now i of course have to add Yellow. Undocumented/Unsupported/Fragile Workarounds There is an undocumented export from DwmApi.dll at entry point 137, which we'll call DwmGetColorizationParameters: HRESULT GetColorizationParameters_Undocumented(out DWMCOLORIZATIONPARAMS params); struct DWMCOLORIZATIONPARAMS { public UInt32 ColorizationColor; public UInt32 ColorizationAfterglow; public UInt32 ColorizationColorBalance; public UInt32 ColorizationAfterglowBalance; public UInt32 ColorizationBlurBalance; public UInt32 ColorizationGlassReflectionIntensity; public UInt32 ColorizationOpaqueBlend; } We're interested in the first parameter: ColorizationColor. We can also read the value out of the registry: HKEY_CURRENT_USER\Software\Microsoft\Windows\DWM ColorizationColor: REG_DWORD = 0x6614A600 So you pick your poison of creating appcompat issues. You can rely on an undocumented API (which is bad, bad, bad, and can go away at any time) use an undocumented registry key (which is also bad, and can go away at any time) See also Is there a list of valid parameter combinations for GetThemeColor / Visual Styles API How does Windows change Aero Glass color? DWM - Colorization Color Handling Using DWMGetColorizationColor Retrieving Aero Glass base color for opaque surface rendering i've been wanting to ask this question for over a year now. i always knew that it's impossible to answer, and that the only way to get anyone to actually pay attention is to have colorful screenshots; developers are attracted to shiny things. But on the downside it means i had to put all kinds of work into making the lures.

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  • certain Smarty tags don't work in OpenX templates

    - by mikez302
    I am on a team that is developing an OpenX plugin, and I am responsible for the UI. I noticed that if I use certain Smarty tags in my template, the app doesn't work and I see an error message, similar to this: Plugin by name 'Html_select_date' was not found in the registry; used paths: default_views_helpers_: /openx/www/admin/plugins/myApp/application/modules/default/views/helpers/ OX_OXP_UI_View_Helper_: /openx/www/admin/plugins/myApp/application/../library/OX/OXP/UI/View/Helper/ OX_UI_View_Helper_: /openx/www/admin/plugins/myApp/application/../library/OX/UI/View/Helper/ Zend_View_Helper_: Zend/View/Helper/ (stack trace) The stack trace looks like this: #0 /openx/www/admin/plugins/myApp/library/Zend/View/Abstract.php(1117): Zend_Loader_PluginLoader-load('Html_select_dat...') #1 /openx/www/admin/plugins/myApp/library/Zend/View/Abstract.php(568): Zend_View_Abstract-_getPlugin('helper', 'html_select_dat...') #2 /openx/www/admin/plugins/myApp/library/OX/UI/Smarty/SmartyWithViewHelper.php(25): Zend_View_Abstract-getHelper('html_select_dat...') #3 /openx/var/templates_compiled/%2Fdefault%2Fviews%2Fscripts%2Findex%2Fview-reports.html^%%E8^E80^E80B56F2%%view-reports.html.php(38): OX_UI_Smarty_SmartyWithViewHelper-callViewHelper('html_select_dat...', Array) #4 /openx/lib/smarty/Smarty.class.php(1274): include('/openx...') #5 /openx/www/admin/plugins/myApp/library/OX/UI/View/SmartyView.php(103): Smarty-fetch('/openx...') #6 /openx/www/admin/plugins/myApp/library/Zend/View/Abstract.php(832): OX_UI_View_SmartyView-_run('/openx...') #7 /openx/www/admin/plugins/myApp/library/OX/UI/View/SmartyView.php(151): Zend_View_Abstract-render('index/view-repo...') #8 /openx/www/admin/plugins/myApp/library/OX/UI/View/Helper/WithViewScript.php(23): OX_UI_View_SmartyView-render('index/view-repo...') #9 /openx/www/admin/plugins/myApp/application/modules/default/views/helpers/ViewReports.php(5): OX_UI_View_Helper_WithViewScript::renderViewScript('index/view-repo...', Array) #10 /openx/www/admin/plugins/myApp/application/modules/default/controllers/IndexController.php(98): Default_Views_Helpers_ViewReports-renderPage() #11 /openx/www/admin/plugins/myApp/library/Zend/Controller/Action.php(512): IndexController-viewReportsAction() #12 /openx/www/admin/plugins/myApp/library/Zend/Controller/Dispatcher/Standard.php(288): Zend_Controller_Action-dispatch('viewReportsActi...') #13 /openx/www/admin/plugins/myApp/library/Zend/Controller/Front.php(945): Zend_Controller_Dispatcher_Standard-dispatch(Object(Zend_Controller_Request_Http), Object(Zend_Controller_Response_Http)) #14 /openx/www/admin/plugins/myApp/application/bootstrap.php(117): Zend_Controller_Front-dispatch() #15 /openx/www/admin/plugins/myApp/public/index.php(7): require('/openx...') #16 {main} This does not happen with all Smarty tags. For example, I can use {if}, {foreach}, or {assign} tags without any problems. But whenever I try to use {html_select_date}, {html_image}, or {html_table}, I get the errors. In case this matters, the programmer who is designing the plugin copied the openXWorkflow plugin and made some changes. I noticed that the openXWorkflow plugin has a file (openx/plugins_repo/openXWorkflow/www/admin/plugins/openXWorkflow/library/OX/UI/Smarty/SmartyCompilerWithViewHelper.php) with a class that overrides the default Smarty compiler, supposedly with the ability to compile shorthands for calling ZF view helpers. That file has a list of Smarty functions, but the list is incomplete. If I add the functions to the list, or simply delete the file, my template works fine, but I don't like to change library files. It may make the app hard to maintain, and I don't know if it will mess up something else. The file has the comment "There is no easy access to the list of Smarty's built-in functions so we need to list them here. HTML-specific functions are not included as we cover HTML generation separately.", so it seems like certain Smarty functions may be disabled on purpose for some reason. Will anything bad happen if I try to use them? If, for example, I want to use the {html_select_date} tag in my template, how would I go about doing that? Keep in mind that much of this stuff is new and unfamiliar to me. This is my first time ever using OpenX or Smarty, and I only have a little bit of experience with the Zend framework. Please let me know if we are using the wrong approach.

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  • Passing unknown amounts of variables using through a string string and eval and multiple functions a

    - by user300797
    I'm not sure how best to describe this problem... In short, I want to use object literal to allow me to pass a random amount of variables in any order to a function. Whilst this is not big deal in theory, in my code, this object literal is passed to a second function call on_change. on_change works comparing an element inner HTML to a string. if it is the same, it sets a time out of to call the function again (this is sort of/almost recursive, but the function dose actually get to end before it is called again). if the elements inner HTML is different from the string, then the third parameter is executed. this will either be a function or a string. either way it will execute. I have tested this function plenty and used it for a while now. how ever, it cannot seem to get the object literal to flow through the function calls... var params = { xpos:'false'}; on_change('window_3_cont_buffer','',' if(Window_manager.windows[3].window_cont_buffer.getElementsByTagName(\'content\')[0].getElementsByTagName(\'p\')[0].innerHTML == \'ERROR\'){ alert(Window_manager.windows[3].window_cont_buffer.getElementsByTagName(\'content\')[0].getElementsByTagName(\'p\')[1].innerHTML); return false; } else { Window_manager.windows[3].load_xml(\'location/view.php?location_ID=3\', \'\', ' + params + ' ); } '); I call this as part of the form submission. after this line, I then call a function to load some content via ajax, which works fine and will trigger the code from the on_change function. I have tested load_xml function it is able to call alert(param.xpos) and get the correct response. I can even added in a check for being undefined so that rest of the times I cam load_xml I don't get swamped with alerts. The load_xml function first set up the on_change function, then calls the function to load the content to a hidden div. Once the AJAX request has updated that DIV, the on_change function should now call the parse_xml function. This pulls out the information from the xml file. How ever... The idea of this object literal param is that it can tell this parse_xml function to ignore certain things. on_change("window_" + this.id + "_cont_buffer", "", "Window_manager.windows[" + this.id + "].parse_xml('" + param + "')"); this is part of load_xml. it works perfectly fine, even with the param bit in there. except, parse_xml dose not seem to be able to use that parameter. I have been able to get it to a point where parse_xml can alert(param) and give [object object] which I would of thought meant that the object litteral had been passed through, but when I try and call alert(param.xpos) I get undefined. I know this is a pig of a problem, and I could get around it by just having the function take a zillion boolean parameters, but its just not practical or elegant. I'm sure you will need to ask me plenty more questions before I can solve this. I will post more complete code, I just cut it down to what is actually going on. Thanks

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  • Background changes by itself and procedure repeats many times until I release the mouse button

    - by Robert
    Dear community, I am a student, and I'm working on a little slots game (if the same random number comes up 3 timed, you win). I use Borland Pascal 7. I use graph to make this a bit more visual, but when I start the game my background turns from black to grey, and the other problem is that if I click the game start button, the game runs many times until I release the mouse button. How can I solve this? Here is my full program: program slots; uses mymouse,graph,crt; var gdriver,gmode,coin:integer; m:mouserec; a,b,c,coins:string; procedure gomb(x1,y1,x2,y2:integer;szoveg:string); var j,n:integer; begin setcolor(blue); rectangle(x1,y1,x2,y2); setfillstyle(1,blue); floodfill(x1+2,y1+2,blue); setcolor(0); outtextxy((x1+x2)div 2 -textwidth(szoveg) div 2 ,(y1+y2) div 2-textheight(szoveg) div 2,szoveg); end; procedure randomal(var a,b,c:string); begin randomize; STR(random(2)+1,a); STR(random(2)+1,b); STR(random(2)+1,c); end; procedure menu; begin; settextstyle(0,0,1); outtextxy(20,10,'Meno menu'); gomb(20,20,90,50,'Teglalap'); gomb(20,60,90,90,'Inditas'); gomb(20,100,90,130,'Harmadik'); gomb(20,140,90,170,'Negyedik'); end; procedure teglalap(x1,x2,y1,y2,tinta:integer); begin setcolor(tinta); rectangle(x1,x2,y1,y2); end; procedure jatek(var a,b,c:string;var coin:integer;coins:string); begin; clrscr; menu; randomal(a,b,c); if ((a=b) AND (b=c)) then coin:=coin+1 else coin:=coin-1; settextstyle(0,0,3); setbkcolor(black); outtextxy(200,20,a); outtextxy(240,20,b); outtextxy(280,20,c); STR(coin,coins); outtextxy(400,400,coins); end; procedure eger; begin; mouseinit; mouseon; menu; repeat getmouse(m); if (m.left) and (m.x20) ANd (m.x<90) and (m.y20) and (m.y<50) then teglalap(90,90,300,300,blue); if (m.left) and (m.x20) AND (m.x<90) and (m.y60) and (m.y<90) then jatek(a,b,c,coin,coins); until ((m.left) and (m.x20) ANd (m.x<140) and (m.y140) and (m.y<170)); end; begin coin:=50; gdriver:=detect; initgraph(gdriver, gmode, ''); eger; end. Thank you very much, Robert

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  • Slow Jquery Animation

    - by Pyronaut
    I have this webpage : http://miloarc.pyrogenicmedia.com/ Which atm is nothing special. It has a few effects but none that break the bank. If you mouse over a tile, it should change it's opacity to give it a fade effect. This is done through the Jquery Animation, not through CSS (I do this so it can fade, instead of being a straight change). Everything looks nice when the page loads, and the fades look perfect. Infact if you drag your mouse all over the place, if gives you a "trail" almost like a snake. Anyway, My next problem is that you will see there is a box in the top left, which is going to tell you information about the tile you are hovering over. This seems to work fine. When you mouse over that information box, it switches it's position (So that you can reach the tiles that were previously hidden underneath it). From my understanding, this is all working fine, and to the letter. However, After one move of the info box (One hover). Viewing the page in Firefox turns slugish. As in, after a successful move of the info box, the fade effects become very stuttered, and it doesn't pick up events as fast meaning you can't draw a "trail" on the screen. Chrome doesn't have this issue. It seems to work fine no matter what. Safari also seems ok. Although I do notice if I move my mouse really fast, it does jump a bit but not as much as firefox. Internet explorer doesn't work at all. Seems to crash the browser... And there is an error with the rounded corner plugin im using (Not sure why...). All in all, I think whatever I'm doing inside my code must be heavily sluggish. But I don't know where it is happening. Here is the full code, but I would advise go to the link to view everything. <script type="text/javascript"> $(document).ready(function() { var WindowWidth = $(window).width(); var WindowMod = WindowWidth % 20; var WindowWidth = WindowWidth - WindowMod; var BoxDimension = WindowWidth / 20; var BoxDimensionFixed = BoxDimension - 12; var dimensions = BoxDimensionFixed + 'px'; $('.gamebutton').each(function(i) { $(this).css('width', dimensions); $(this).css('height', dimensions); }); var OuterDivHeight = BoxDimension * 10; var TopMargin = ($(window).height() - OuterDivHeight) / 2; var OuterDivWidth = BoxDimension * 20; var LeftMargin = ($(window).width() - OuterDivWidth) / 2; $('#gamePort').css('margin-top', TopMargin).css('margin-left', LeftMargin).css('margin-right', LeftMargin); $('.gamebutton img').each(function(i) { $(this).hover( function () { $(this).animate({'opacity': 0.65}); }, function () { $(this).animate({'opacity': 1}); } ); }); $('.rounded').corners(); $('.gamebutton').each(function(i) { $(this).hover(function() { $('.gameTitlePopup').html($(this).attr('title')); FadeActive(); }); }); function FadeActive() { $('.activeInfo').fadeIn('slow'); } $('#gameInfoLeft').hover(function() { $(this).removeClass('activeInfo'); $(this).fadeOut('slow', function() { $('#gameInfoRight').addClass('activeInfo'); FadeActive(); }); }); $('#gameInfoRight').hover(function() { $(this).removeClass('activeInfo'); $(this).fadeOut('slow', function() { $('#gameInfoLeft').addClass('activeInfo'); FadeActive(); }); }); }); </script> Thanks for any help :).

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  • Export GridView to Excel

    - by nCdy
    using Matt's util code (a bit edited for Unicode text) public class GridViewExportUtil { /// <param name="fileName"></param> /// <param name="gv"></param> public static void Export(string fileName, GridView gv) { HttpContext.Current.Response.Clear(); HttpContext.Current.Response.ContentType = "application/ms-excel"; HttpContext.Current.Response.Cache.SetCacheability(HttpCacheability.NoCache); HttpContext.Current.Response.Charset = System.Text.Encoding.Unicode.EncodingName; HttpContext.Current.Response.ContentEncoding = System.Text.Encoding.Unicode; HttpContext.Current.Response.BinaryWrite(System.Text.Encoding.Unicode.GetPreamble()); HttpContext.Current.Response.AddHeader( "content-disposition", string.Format(//"content-disposition", "attachment; filename=Report.xml"));//, fileName)); // Need .XLS file using (StringWriter sw = new StringWriter()) { using (HtmlTextWriter htw = new HtmlTextWriter(sw)) { // Create a form to contain the grid Table table = new Table(); // add the header row to the table if (gv.HeaderRow != null) { GridViewExportUtil.PrepareControlForExport(gv.HeaderRow); table.Rows.Add(gv.HeaderRow); } // add each of the data rows to the table foreach (GridViewRow row in gv.Rows) { GridViewExportUtil.PrepareControlForExport(row); table.Rows.Add(row); } // add the footer row to the table if (gv.FooterRow != null) { GridViewExportUtil.PrepareControlForExport(gv.FooterRow); table.Rows.Add(gv.FooterRow); } // render the table into the htmlwriter table.RenderControl(htw); // render the htmlwriter into the response HttpContext.Current.Response.Write(sw.ToString()); HttpContext.Current.Response.End(); } } } /// <summary> /// Replace any of the contained controls with literals /// </summary> /// <param name="control"></param> private static void PrepareControlForExport(Control control) { for (int i = 0; i < control.Controls.Count; i++) { Control current = control.Controls[i]; if (current is LinkButton) { control.Controls.Remove(current); control.Controls.AddAt(i, new LiteralControl((current as LinkButton).Text)); } else if (current is ImageButton) { control.Controls.Remove(current); control.Controls.AddAt(i, new LiteralControl((current as ImageButton).AlternateText)); } else if (current is HyperLink) { control.Controls.Remove(current); control.Controls.AddAt(i, new LiteralControl((current as HyperLink).Text)); } else if (current is DropDownList) { control.Controls.Remove(current); control.Controls.AddAt(i, new LiteralControl((current as DropDownList).SelectedItem.Text)); } else if (current is CheckBox) { control.Controls.Remove(current); control.Controls.AddAt(i, new LiteralControl((current as CheckBox).Checked ? "True" : "False")); } if (current.HasControls()) { GridViewExportUtil.PrepareControlForExport(current); } } } Question : How to make downloaded file editable (not Read only) And ... XLS wont opens with Unicode format. When I changing format to UTF8 I can't see Russian words :S Second question : How to make Unicode for .xls Third question : How can I save table lines ? Thank you.

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  • Representing game states in Tic Tac Toe

    - by dacman
    The goal of the assignment that I'm currently working on for my Data Structures class is to create a of Quantum Tic Tac Toe with an AI that plays to win. Currently, I'm having a bit of trouble finding the most efficient way to represent states. Overview of current Structure: AbstractGame Has and manages AbstractPlayers (game.nextPlayer() returns next player by int ID) Has and intializes AbstractBoard at the beginning of the game Has a GameTree (Complete if called in initialization, incomplete otherwise) AbstractBoard Has a State, a Dimension, and a Parent Game Is a mediator between Player and State, (Translates States from collections of rows to a Point representation Is a StateConsumer AbstractPlayer Is a State Producer Has a ConcreteEvaluationStrategy to evaluate the current board StateTransveralPool Precomputes possible transversals of "3-states". Stores them in a HashMap, where the Set contains nextStates for a given "3-state" State Contains 3 Sets -- a Set of X-Moves, O-Moves, and the Board Each Integer in the set is a Row. These Integer values can be used to get the next row-state from the StateTransversalPool SO, the principle is Each row can be represented by the binary numbers 000-111, where 0 implies an open space and 1 implies a closed space. So, for an incomplete TTT board: From the Set<Integer> board perspective: X_X R1 might be: 101 OO_ R2 might be: 110 X_X R3 might be: 101, where 1 is an open space, and 0 is a closed space From the Set<Integer> xMoves perspective: X_X R1 might be: 101 OO_ R2 might be: 000 X_X R3 might be: 101, where 1 is an X and 0 is not From the Set<Integer> oMoves perspective: X_X R1 might be: 000 OO_ R2 might be: 110 X_X R3 might be: 000, where 1 is an O and 0 is not Then we see that x{R1,R2,R3} & o{R1,R2,R3} = board{R1,R2,R3} The problem is quickly generating next states for the GameTree. If I have player Max (x) with board{R1,R2,R3}, then getting the next row-states for R1, R2, and R3 is simple.. Set<Integer> R1nextStates = StateTransversalPool.get(R1); The problem is that I have to combine each one of those states with R1 and R2. Is there a better data structure besides Set that I could use? Is there a more efficient approach in general? I've also found Point<-State mediation cumbersome. Is there another approach that I could try there? Thanks! Here is the code for my ConcretePlayer class. It might help explain how players produce new states via moves, using the StateProducer (which might need to become StateFactory or StateBuilder). public class ConcretePlayerGeneric extends AbstractPlayer { @Override public BinaryState makeMove() { // Given a move and the current state, produce a new state Point playerMove = super.strategy.evaluate(this); BinaryState currentState = super.getInGame().getBoard().getState(); return StateProducer.getState(this, playerMove, currentState); } } EDIT: I'm starting with normal TTT and moving to Quantum TTT. Given the framework, it should be as simple as creating several new Concrete classes and tweaking some things.

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  • Problem with memset after an instance of a user defined class is created and a file is opened

    - by Liberalkid
    I'm having a weird problem with memset, that was something to do with a class I'm creating before it and a file I'm opening in the constructor. The class I'm working with normally reads in an array and transforms it into another array, but that's not important. The class I'm working with is: #include <vector> #include <algorithm> using namespace std; class PreProcess { public: PreProcess(char* fileName,char* outFileName); void SortedOrder(); private: vector< vector<double > > matrix; void SortRow(vector<double> &row); char* newFileName; vector< pair<double,int> > rowSorted; }; The other functions aren't important, because I've stopped calling them and the problem persists. Essentially I've narrowed it down to my constructor: PreProcess::PreProcess(char* fileName,char* outFileName):newFileName(outFileName){ ifstream input(fileName); input.close(); //this statement is inconsequential } I also read in the file in my constructor, but I've found that the problem persists if I don't read in the matrix and just open the file. Essentially I've narrowed it down to if I comment out those two lines the memset works properly, otherwise it doesn't. Now to the context of the problem I'm having with it: I wrote my own simple wrapper class for matrices. It doesn't have much functionality, I just need 2D arrays in the next part of my project and having a class handle everything makes more sense to me. The header file: #include <iostream> using namespace std; class Matrix{ public: Matrix(int r,int c); int &operator()(int i,int j) {//I know I should check my bounds here return matrix[i*columns+j]; } ~Matrix(); const void Display(); private: int *matrix; const int rows; const int columns; }; Driver: #include "Matrix.h" #include <string> using namespace std; Matrix::Matrix(int r,int c):rows(r),columns(c) { matrix=new int[rows*columns]; memset(matrix,0,sizeof(matrix)); } const void Matrix::Display(){ for(int i=0;i<rows;i++){ for(int j=0;j<columns;j++) cout << (*this)(i,j) << " "; cout << endl; } } Matrix::~Matrix() { delete matrix; } My main program runs: PreProcess test1(argv[1],argv[2]); //test1.SortedOrder(); Matrix test(10,10); test.Display(); And when I run this with the input line uncommented I get: 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 -1371727776 32698 -1 0 0 0 0 0 6332656 0 -1 -1 0 0 6332672 0 0 0 0 0 0 0 0 0 0 0 0 0 -1371732704 32698 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 I really don't have a clue what's going on in memory to cause this, on a side note if I replace memset with: for(int i=0;i<rows*columns;i++) *(matrix+i) &= 0x0; Then it works perfectly, it also works if I don't open the file. If it helps I'm running GCC 64-bit version 4.2.4 on Ubuntu.I assume there's some functionality of memset that I'm not properly understanding.

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  • What is "elegant" code?

    - by Breton
    I see a lot of lip service and talk about the most "elegant" way to do this or that. I think if you spend enough time programming you begin to obtain a sort of intuitive feel for what it is we call "elegance". But I'm curious. Even if we can look at a bit of code, and say instinctively "That's elegant", or "That's messy", I wonder if any of us really understands what that means. Is there a precise definition for this "elegance" we keep referring to? If there is, what is it? Now, what I mean by a precise definition, is a series of statements which can be used to derive questions about a peice of code, or a program as a whole, and determine objectively, or as objectively as possible, whether that code is "elegant" or not. May I assert, that perhaps no such definition exists, and it's all just personal preference. In this case, I ask you a slightly different question: Is there a better word for "elegance", or a better set of attributes to use for judging code quality that is perhaps more objective than merely appealing to individual intuition and taste? Perhaps code quality is a matter of taste, and the answer to both of my questions is "no". But I can't help but feel that we could be doing better than just expressing wishy washy feelings about our code quality. For example, user interface design is something that to a broad range of people looks for all the world like a field of study that oughtta be 100% subjective matter of taste. But this is shockingly and brutally not the case, and there are in fact many objective measures that can be applied to a user interface to determine its quality. A series of tests could be written to give a definitive and repeatable score to user interface quality. (See GOMS, for instance). Now, okay. is Elegance simply "code quality" or is it something more? Is it something that can be measured? Or is it a matter of taste? Does our profession have room for taste? Maybe I'm asking the wrong questions altogether. Help me out here. Bonus Round If there is such a thing as elegance in code, and that concept is useful, do you think that justifies classifying the field of programming as an "Art" capital A, or merely a "craft". Or is it just an engineering field populated by a bunch of wishful thinking humans? Consider this question in the light of your thoughts about the elegance question. Please note that there is a distinction between code which is considered "art" in itself, and code that was written merely in the service of creating an artful program. When I ask this question, I ask if the code itself justifies calling programming an art. Bounty Note I liked the answers to this question so much, I think I'd like to make a photographic essay book from it. Released as a free PDF, and published on some kind of on demand printing service of course, such as "zazz" or "tiggle" or "printley" or something . I'd like some more answers, please!

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  • Issues writing to serial port on MAC OSX using unistd.h in c

    - by Schuyler
    I am trying to write to a bluetooth device on MAC OSX using the unistd.h Linux functions in c. I am connecting fine and writing the first few bytes with success. When I try to write other commands to it (there are bytes added to the write buffer every 15ms), I don't see any results even though the write() function returns 1 (write success). If you start a write and it doesn't finish by the time you try to start another write (since it is non-blocking), could that possibly screw up the initial write? (If so, is there any way to check if a write has completed?) That is the only thing I can think of since the writes are occurring fairly frequently and the first two are successfully sent. qwbyte() simply adds a byte to the output array and increments its length The open port function: BAMid = -1; struct termios options; struct termios originalTTYAttrs; // Open the serial port read/write, nonblocking, with no controlling terminal, and don't wait for a connection. BAMid = open(strPath, O_RDWR | O_NOCTTY | O_NONBLOCK); if (BAMid == -1) { printf("Error opening serial port %s - %s(%d).\n", strPath, strerror(errno), errno); goto error; } // Issue TIOCEXCL ioctl to prevent additional opens except by root-owned processes. if (ioctl(BAMid, TIOCEXCL) == -1) { printf("Error setting TIOCEXCL on %s - %s(%d).\n", strPath, strerror(errno), errno); goto error; } // Get the current options and save them so we can restore the default settings later. if (tcgetattr(BAMid, &originalTTYAttrs) == -1) { printf("Error getting tty attributes %s - %s(%d).\n", strPath, strerror(errno), errno); goto error; } // The serial port attributes such as timeouts and baud rate are set by modifying the termios // structure and then calling tcsetattr() to cause the changes to take effect. Note that the // changes will not become effective without the tcsetattr() call. options = originalTTYAttrs; // Set raw input (non-canonical) mode, with reads blocking until either a single character // has been received or a one second timeout expires. [should be moot since we are leaving it as nonblocking] cfmakeraw(&options); options.c_cc[VMIN] = 1; options.c_cc[VTIME] = 10; cfsetspeed(&options, B57600); // Set 57600 baud options.c_cflag |= CS8; // Use 8 bit words // Cause the new options to take effect immediately. if (tcsetattr(BAMid, TCSANOW, &options) == -1) { printf("Error setting tty attributes %s - %s(%d).\n", strPath, strerror(errno), errno); goto error; } //flush old transmissions if (tcflush(BAMid,TCIOFLUSH) == -1) { printf("Error flushing BAM serial port - %s(%d).\n", strerror(errno), errno); } oBufLength = 0; // Ask it to start if (! qwbyte(CmdStart) ) { goto error; } if (! qwbyte(CmdFull) ) { goto error; } //this transmit works txbytes(); printf("success opening port!"); return -1; // Failure path error: if (BAMid != -1) { close(BAMid); } printf("returning an error--%d",errno); return errno; } The write function (txbytes): int i, bufSize, numBytes; if(oBufLength != 0) { //if the output array isn't empty //duplicating the output array and its size so it can //be overwritten while this write is occuring printf("about to transmit: "); for(i = 0; i < oBufLength; i++) { printf(" %u",oBuf[i]); tempBuf[i] = oBuf[i]; } printf("\n"); bufSize = oBufLength; oBufLength = 0; numBytes = write(BAMid, &tempBuf, bufSize); printf("bytes written = %d\n",numBytes); if (numBytes == -1) { printf("Error writing to port - %s(%d).\n", strerror(errno), errno); } return (numBytes 0); } else { return 0; }

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  • Qt, MSVC, and /Zc:wchar_t- == I want to blow up the world

    - by Noah Roberts
    So Qt is compiled with /Zc:wchar_t- on windows. What this means is that instead of wchar_t being a typedef for some internal type (__wchar_t I think) it becomes a typedef for unsigned short. The really cool thing about this is that the default for MSVC is the opposite, which of course means that the libraries you're using are likely compiled with wchar_t being a different type than Qt's wchar_t. This doesn't become an issue of course until you try to use something like std::wstring in your code; especially when one or more libraries have functions that accept it as parameters. What effectively happens is that your code happily compiles but then fails to link because it's looking for definitions using std::wstring<unsigned short...> but they only contain definitions expecting std::wstring<__wchar_t...> (or whatever). So I did some web searching and ran into this link: http://bugreports.qt.nokia.com/browse/QTBUG-6345 Based on the statement by Thiago Macieira, "Sorry, we will not support building Qt like this," I've been worried that fixing Qt to work like everything else might cause some problem and have been trying to avoid it. We recompiled all of our support libraries with the /Zc:wchar_t- flag and have been fairly content with that until a couple days ago when we started trying to port over (we're in the process of switching from Wx to Qt) some serialization code. Because of how win32 works, and because Wx just wraps win32, we've been using std::wstring to represent string data with the intent of making our product as i18n ready as possible. We did some testing and Wx did not work with multibyte characters when trying to print special stuff (even not so special stuff like the degree symbol was an issue). I'm not so sure that Qt has this problem since QString isn't just a wrapper to the underlying _TCHAR type but is a Unicode monster of some sort. At any rate, the serialization library in boost has compiled parts. We've attempted to recompile boost with /Zc:wchar_t- but so far our attempts to tell bjam to do this have gone unheeded. We're at an impasse. From where I'm sitting I have three options: Recompile Qt and hope it works with /Zc:wchar_t. There's some evidence around the web that others have done this but I have no way of predicting what will happen. All attempts to ask Qt people on forums and such have gone unanswered. Hell, even in that very bug report someone asks why and it just sat there for a year. Keep fighting with bjam until it listens. Right now I've got someone under me doing that and I have more experience fighting with things to get what I want but I do have to admit to getting rather tired of it. I'm also concerned that I'll KEEP running into this issue just because Qt wants to be a c**t. Stop using wchar_t for anything. Unfortunately my i18n experience is pretty much 0 but it seems to me that I just need to find the right to/from function in QString (it has a BUNCH) to encode the Unicode into 8-bytes and visa-versa. UTF8 functions look promising but I really want to be sure that no data will be lost if someone from Zimbabfuckegypt starts writing in their own language and the documentation in QString frightens me a little into thinking that could happen. Of course, I could always run into some library that insists I use wchar_t and then I'm back to 1 or 2 but I rather doubt that would happen. So, what's my question... Which of these options is my best bet? Is Qt going to eventually cause me to gouge out my own eyes because I decided to compile it with /Zc:wchar_t anyway? What's the magic incantation to get boost to build with /Zc:wchar_t- and will THAT cause permanent mental damage? Can I get away with just using the standard 8-bit (well, 'common' anyway) character classes and be i18n compliant/ready? How do other Qt developers deal with this mess?

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  • How to structure a Kohana MVC application with dynamically added fields and provide validation and f

    - by Matt H
    I've got a bit of a problem. I have a Kohana application that has dynamically added fields. The fields that are added are called DISA numbers. In the model I look these up and the result is returned as an array. I encode the array into a JSON string and use JQuery to populate them The View knows the length of the array and so creates as many DISA elements as required before display. See the code below for a summary of how that works. What I'm finding is that this is starting to get difficult to manage. The code is becoming messy. Error handling of this type of dynamic content is ending up being spread all over the place. Not only that, it doesn't work how I want. What you see here is just a small snippet of code. For error handling I am using the validation library. I started by using add_rules on all the fields that come back in the post. As they are always phone numbers I set a required rule (when it's there) and a digit rule on the validation-as_array() keys. That works. The difficulty is actually giving it back to the view. i.e. dynamically added javascript field. Submits back to form. Save contents into a session. View has to load up fields from database + those from the previous post and signal the fields that have problems. It's all quite messy and I'm getting this code spread through both the view the controller and the model. So my question is. Have you done this before in Kohana and how have you handled it? There must be an easier way right? Code snippet. -- edit.php -- public function phone($id){ ... $this->template->content->disa_numbers = $phones->fetch_disa_numbers($this->account, $id); ... } -- phones.php -- public function fetch_disa_numbers($account, $id) { $query = $this->db->query("SELECT id, cid_in FROM disa WHERE owner_ext=?", array($id)); if (!$query){ return ''; } return $query; } -- edit_phones.php --- <script type="text/javascript"> var disaId = 1; function delDisaNumber(element){ /* Put 'X_' on the front of the element name to mark this for deletion */ $(element).prev().attr('name', 'X_'+$(element).prev().attr('name')); $(element).parent().hide(); } function addDisaNumber(){ /* input name is prepended with 'N_' which means new */ $("#disa_numbers").append("<li><input name='N_disa"+disaId+"' id='disa'"+ "type='text'/><a class='hide' onClick='delDisaNumber(this)'></a></li>"); disaId++; } </script> ... <php echo form::open("edit/saveDisaNumbers/".$phone, array("class"=>"section", "id"=>"disa_form")); echo form::open_fieldset(array("class"=>"balanced-grid")); ?> <ul class="fields" id="disa_numbers"> <?php $disaId = 1; foreach ( $disa_numbers as $disa_number ){ echo '<li>'; echo form::input('disa'.$disaId, $disa_number->cid_in); echo'<a class="hide" onclick="delDisaNumber(this)"></a>'; echo "</li>"; $disaId++; } ?> </ul> <button type="button"onclick="addDisaNumber()"><a class="add"></a>Add number</button> <?php echo form::submit('submit', 'Save'); echo form::close(); ?>

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  • Adding interactions to admin pages generated by the admin generator

    - by Stick it to THE MAN
    I am using Symfony 1.2.9 (with Propel ORM) to create a website. I have started using the admin generator to implement the admin functionality. I have come accross a slight 'problem' however. My models are related (e.g. one table may have several 1:N relations and N:N relations). I have not found a way to address this satisfactorily yet. As a tactical solution (for list views), I have decided to simply show the parent object, and then add interactions to show the related objects. I'll use a Blog model to illustrate this. Here are the relationships for a blog model: N:M relationship with Blogroll (models a blog roll) 1:N relationship with Blogpost (models a post submitted to a blog) I had originally intended on displaying the (paged) blogpost list for a blog,, when it was selected, using AJAX, but I am struggling enough with the admin generator as it is, so I have shelved that idea - unless someone is kind enough to shed some light on how to do this. Instead, what I am now doing (as a tactical/interim soln), is I have added interactions to the list view which allow a user to: View a list of the blog roll for the blog on that row View a list of the posts for the blog on that row Add a post for the blog on tha row In all of the above, I have written actions that will basically forward the request to the approriate action (admin generated). However, I need to pass some parameters (like the blog id etc), so that the correct blog roll or blog post list etc is returned. I am sure there is a better way of doing what I want to do, but in case there isn't here are my questions: How may I obtain the object that relates to a specific row (of the clicked link) in the list view (e.g. the blog object in this example) Once I have the object, I may choose to extract various fields: id etc. How can I pass these arguments to the admin generated action ? Regarding the second question, my guess is that this may be the way to do it (I may be wrong) public function executeMyAddedBlogRollInteractionLink(sfWebRequest $request) { // get the object *somehow* (I'm guessing this may work) $object = $this->getRoute()->getObject(); // retrieve the required parameters from the object, and build a query string $query_str=$object->getId(); //forward the request to the generated code (action to display blogroll list in this case) $this->forward('backendmodulename',"getblogrolllistaction?params=$query_string"); } This feels like a bit of a hack, but I'm not sure how else to go about it. I'm also not to keen on sending params (which may include user_id etc via a GET, even a POST is not that much safer, since it is fairly sraightforward to see what requests a browser is making). if there is a better way than what I suggest above to implement this kind of administration that is required for objects with 1 or more M:N relationships, I will be very glad to hear the "recommended" way of going about it. I remember reading about marking certain actions as internal. i.e. callable from only within the app. I wonder if that would be useful in this instance?

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  • flash as3, fade in/out layering problem

    - by Jackson Smith
    Ok, what im trying to do is make a day to night cycle behind my landscape. There is a sun and a moon, they rotate in a circle on opposite sides. (i.e. the sun is up when the moon is down and vice versa) when the sun is coming up it should fade from the night movieclip to the dawn movieclip, then when the sun is up a little bit more, fade into the day moviclip, this works quite well, but, for some reason, when it gets to the sunset, it just wont work :/ and the same goes for when it goes from the sunset to night :/ any and all healp is greatly appreciated, ive spent 5 hours trying to figure this out and cant! please help! stage.addEventListener(Event.ENTER_FRAME, daynightcycle) //setChildIndex(night, getChildIndex(day)); setChildIndex(sunset, 0); setChildIndex(day, 1); setChildIndex(dawn, 2); setChildIndex(night, 3); function daynightcycle(e:Event):void { if(sun.currentLabel == "dawn") { setChildIndex(sunset, 0); setChildIndex(day, 1); setChildIndex(dawn, 2); setChildIndex(night, 3); stage.addEventListener(Event.ENTER_FRAME, nightTdawn); }else if(sun.currentLabel == "sunset") { setChildIndex(dawn, 0); setChildIndex(night, 1); setChildIndex(sunset, 2); setChildIndex(day, 3); stage.addEventListener(Event.ENTER_FRAME, dayTsunset); }else if(sun.currentLabel == "night") { setChildIndex(day, 0); setChildIndex(dawn, 1); setChildIndex(night, 2); setChildIndex(sunset, 3); stage.addEventListener(Event.ENTER_FRAME, sunsetTnight); }else if(sun.currentLabel == "day") { setChildIndex(night, 0); setChildIndex(sunset, 1); setChildIndex(day, 2); setChildIndex(dawn, 3); stage.addEventListener(Event.ENTER_FRAME, dawnTday); }else if(sun.currentLabel == "switch") { stage.addEventListener(Event.ENTER_FRAME, switchLayers); } } function nightTdawn(e:Event):void { if(night.alpha != 0) { night.alpha -= 0.01; }else { stage.removeEventListener(Event.ENTER_FRAME, nightTdawn); night.alpha = 100; //setChildIndex(night, getChildIndex(sunset)); } } function dayTsunset(e:Event):void { if(day.alpha != 0) { day.alpha -= 0.01; }else { stage.removeEventListener(Event.ENTER_FRAME, dayTsunset); day.alpha = 100; //setChildIndex(day, getChildIndex(dawn)); } //day.visible = false; //sunset.visible = true; } function sunsetTnight(e:Event):void { if(sunset.alpha != 0) { sunset.alpha -= 0.01; }else{ stage.removeEventListener(Event.ENTER_FRAME, sunsetTnight); sunset.alpha = 100; //setChildIndex(sunset, (getChildIndex(day))); } //sunset.visible = false; //night.visible = true; } function dawnTday(e:Event):void { sunset.visible = true; day.visible = true; if(dawn.alpha != 0) { dawn.alpha -= 0.01; }else{ stage.removeEventListener(Event.ENTER_FRAME, dawnTday); dawn.alpha = 100; //setChildIndex(dawn, (getChildIndex(night))); } } function switchLayers(e:Event):void { setChildIndex(dawn, 0); setChildIndex(night, 1); setChildIndex(sunset, 2); setChildIndex(day, 3); night.alpha = 100; sunset.alpha = 100; day.alpha = 100; dawn.alpha = 100; stage.removeEventListener(Event.ENTER_FRAME, switchLayers); }

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  • Problem exporting NSOpenGLView pixel data to some image file formats using ImageKit & CGImageDestina

    - by walkytalky
    I am developing an application to visualise some experimental data. One of its functions is to render the data in an NSOpenGLView subclass, and allow the resulting image to be exported to a file or copied to the clipboard. The view exports the data as an NSImage, generated like this: - (NSImage*) image { NSBitmapImageRep* imageRep; NSImage* image; NSSize viewSize = [self bounds].size; int width = viewSize.width; int height = viewSize.height; [self lockFocus]; [self drawRect:[self bounds]]; [self unlockFocus]; imageRep=[[[NSBitmapImageRep alloc] initWithBitmapDataPlanes:NULL pixelsWide:width pixelsHigh:height bitsPerSample:8 samplesPerPixel:4 hasAlpha:YES isPlanar:NO colorSpaceName:NSDeviceRGBColorSpace bytesPerRow:width*4 bitsPerPixel:32] autorelease]; [[self openGLContext] makeCurrentContext]; glReadPixels(0,0,width,height,GL_RGBA,GL_UNSIGNED_BYTE,[imageRep bitmapData]); image=[[[NSImage alloc] initWithSize:NSMakeSize(width,height)] autorelease]; [image addRepresentation:imageRep]; [image setFlipped:YES]; // this is deprecated in 10.6 [image lockFocusOnRepresentation:imageRep]; // this will flip the rep [image unlockFocus]; return image; } Copying uses this image very simply, like this: - (IBAction) copy:(id) sender { NSImage* img = [self image]; NSPasteboard* pb = [NSPasteboard generalPasteboard]; [pb clearContents]; NSArray* copied = [NSArray arrayWithObject:img]; [pb writeObjects:copied]; } For file writing, I use the ImageKit IKSaveOptions accessory panel to set the output file type and associated options, then use the following code to do the writing: NSImage* glImage = [glView image]; NSRect rect = [glView bounds]; rect.origin.x = rect.origin.y = 0; img = [glImage CGImageForProposedRect:&rect context:[NSGraphicsContext currentContext] hints:nil]; if (img) { NSURL* url = [NSURL fileURLWithPath: path]; CGImageDestinationRef dest = CGImageDestinationCreateWithURL((CFURLRef)url, (CFStringRef)newUTType, 1, NULL); if (dest) { CGImageDestinationAddImage(dest, img, (CFDictionaryRef)[imgSaveOptions imageProperties]); CGImageDestinationFinalize(dest); CFRelease(dest); } } (I've trimmed a bit of extraneous code here, but nothing that would affect the outcome as far as I can see. The newUTType comes from the IKSaveOptions panel.) This works fine when the file is exported as GIF, JPEG, PNG, PSD or TIFF, but exporting to PDF, BMP, TGA, ICNS and JPEG-2000 produces a red colour artefact on part of the image. Example images are below, the first exported as JPG, the second as PDF. Copy to clipboard does not exhibit this red stripe with the current implementation of image, but it did with the original implementation, which generated the imageRep using NSCalibratedRGBColorSpace rather than NSDeviceRGBColorSpace. So I'm guessing there's some issue with the colour representation in the pixels I get from OpenGL that doesn't get through the subsequent conversions properly, but I'm at a loss as to what to do about it. So, can anyone tell me (i) what is causing this, and (ii) how can I make it go away? I don't care so much about all of the formats but I'd really like at least PDF to work.

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  • How do you stop scripters from slamming your website hundreds of times a second?

    - by davebug
    [update] I've accepted an answer, as lc deserves the bounty due to the well thought-out answer, but sadly, I believe we're stuck with our original worst case scenario: CAPTCHA everyone on purchase attempts of the crap. Short explanation: caching / web farms make it impossible for us to actually track hits, and any workaround (sending a non-cached web-beacon, writing to a unified table, etc.) slows the site down worse than the bots would. There is likely some pricey bit of hardware from Cisco or the like that can help at a high level, but it's hard to justify the cost if CAPTCHAing everyone is an alternative. I'll attempt to do a more full explanation in here later, as well as cleaning this up for future searchers (though others are welcome to try, as it's community wiki). I've added bounty to this question and attempted to explain why the current answers don't fit our needs. First, though, thanks to all of you who have thought about this, it's amazing to have this collective intelligence to help work through seemingly impossible problems. I'll be a little more clear than I was before: This is about the bag o' crap sales on woot.com. I'm the president of Woot Workshop, the subsidiary of Woot that does the design, writes the product descriptions, podcasts, blog posts, and moderates the forums. I work in the css/html world and am only barely familiar with the rest of the developer world. I work closely with the developers and have talked through all of the answers here (and many other ideas we've had). Usability of the site is a massive part of my job, and making the site exciting and fun is most of the rest of it. That's where the three goals below derive. CAPTCHA harms usability, and bots steal the fun and excitement out of our crap sales. To set up the scenario a little more, bots are slamming our front page tens of times a second screenscraping (and/or scanning our rss) for the Random Crap sale. The moment they see that, it triggers a second stage of the program that logs in, clicks I want One, fills out the form, and buys the crap. In current (2/6/2009) order of votes: lc: On stackoverflow and other sites that use this method, they're almost always dealing with authenticated (logged in) users, because the task being attempted requires that. On Woot, anonymous (non-logged) users can view our home page. In other words, the slamming bots can be non-authenticated (and essentially non-trackable except by IP address). So we're back to scanning for IPs, which a) is fairly useless in this age of cloud networking and spambot zombies and b) catches too many innocents given the number of businesses that come from one IP address (not to mention the issues with non-static IP ISPs and potential performance hits to trying to track this). Oh, and having people call us would be the worst possible scenario. Can we have them call you? BradC Ned Batchelder's methods look pretty cool, but they're pretty firmly designed to defeat bots built for a network of sites. Our problem is bots are built specifically to defeat our site. Some of these methods could likely work for a short time until the scripters evolved their bots to ignore the honeypot, screenscrape for nearby label names instead of form ids, and use a javascript-capable browser control. lc again "Unless, of course, the hype is part of you

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  • Use QuickCheck by generating primes

    - by Dan
    Background For fun, I'm trying to write a property for quick-check that can test the basic idea behind cryptography with RSA. Choose two distinct primes, p and q. Let N = p*q e is some number relatively prime to (p-1)(q-1) (in practice, e is usually 3 for fast encoding) d is the modular inverse of e modulo (p-1)(q-1) For all x such that 1 < x < N, it is always true that (x^e)^d = x modulo N In other words, x is the "message", raising it to the eth power mod N is the act of "encoding" the message, and raising the encoded message to the dth power mod N is the act of "decoding" it. (The property is also trivially true for x = 1, a case which is its own encryption) Code Here are the methods I have coded up so far: import Test.QuickCheck -- modular exponentiation modExp :: Integral a => a -> a -> a -> a modExp y z n = modExp' (y `mod` n) z `mod` n where modExp' y z | z == 0 = 1 | even z = modExp (y*y) (z `div` 2) n | odd z = (modExp (y*y) (z `div` 2) n) * y -- relatively prime rPrime :: Integral a => a -> a -> Bool rPrime a b = gcd a b == 1 -- multiplicative inverse (modular) mInverse :: Integral a => a -> a -> a mInverse 1 _ = 1 mInverse x y = (n * y + 1) `div` x where n = x - mInverse (y `mod` x) x -- just a quick way to test for primality n `divides` x = x `mod` n == 0 primes = 2:filter isPrime [3..] isPrime x = null . filter (`divides` x) $ takeWhile (\y -> y*y <= x) primes -- the property prop_rsa (p,q,x) = isPrime p && isPrime q && p /= q && x > 1 && x < n && rPrime e t ==> x == (x `powModN` e) `powModN` d where e = 3 n = p*q t = (p-1)*(q-1) d = mInverse e t a `powModN` b = modExp a b n (Thanks, google and random blog, for the implementation of modular multiplicative inverse) Question The problem should be obvious: there are way too many conditions on the property to make it at all usable. Trying to invoke quickCheck prop_rsa in ghci made my terminal hang. So I've poked around the QuickCheck manual a bit, and it says: Properties may take the form forAll <generator> $ \<pattern> -> <property> How do I make a <generator> for prime numbers? Or with the other constraints, so that quickCheck doesn't have to sift through a bunch of failed conditions? Any other general advice (especially regarding QuickCheck) is welcome.

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  • Why isn't my algorithm for find the biggest and smallest inputs working?

    - by Matt Ellen
    I have started a new job, and with it comes a new language: Ironpython. Thankfully a good language :D Before starting I got to grips with Python on the whole, but that was only a week's worth of learning. Now I'm writing actual code. I've been charged with writing an algorithm that finds the best input parameter to collect data with. The basic algorithm is (as I've been instructed): Set the input parameter to a good guess Start collecting data When data is available stop collecting find the highest point If the point before this (i.e. for the previous parameter value) was higher and the point before that was lower then we've found the max otherwise the input parameter is increased by the initial guess. goto 2 If the max is found then the min needs to be found. To do this the algorithm carries on increasing the input, but by 1/10 of the max, until the current point is greater than the previous point and the point before that is also greater. Once the min is found then the algorithm stops. Currently I have a simplified data generator outputting the sin of the input, so that I know that the min value should be PI and the max value should be PI/2 The main Python code looks like this (don't worry, this is just for my edification, I don't write real code like this): import sys sys.path.append(r"F:\Programming Source\C#\PythonHelp\PythonHelp\bin\Debug") import clr clr.AddReferenceToFile("PythonHelpClasses.dll") import PythonHelpClasses from PHCStruct import Helper from System import Math helper = Helper() def run(): b = PythonHelpClasses.Executor() a = PythonHelpClasses.HasAnEvent() b.Input = 0.0 helper.__init__() def AnEventHandler(e): b.Stop() h = helper h.lastLastVal, h.lastVal, h.currentVal = h.lastVal, h.currentVal, e.Number if h.lastLastVal < h.lastVal and h.currentVal < h.lastVal and h.NotPast90: h.NotPast90 = False h.bestInput = h.lastInput inputInc = 0.0 if h.NotPast90: inputInc = Math.PI/10.0 else: inputInc = h.bestInput/10.0 if h.lastLastVal > h.lastVal and h.currentVal > h.lastVal and h.NotPast180: h.NotPast180 = False if h.NotPast180: h.lastInput, b.Input = b.Input, b.Input + inputInc b.Start(a) else: print "Best input:", h.bestInput print "Last input:", h.lastInput b.Stop() a.AnEvent += AnEventHandler b.Start(a) PHCStruct.py: class Helper(): def __init__(self): self.currentVal = 0 self.lastVal = 0 self.lastLastVal = 0 self.NotPast90 = True self.NotPast180 = True self.bestInput = 0 self.lastInput = 0 PythonHelpClasses has two small classes I wrote in C# before I realised how to do it in Ironpython. Executor runs a delegate asynchronously while it's running member is true. The important code: public void Start(HasAnEvent hae) { running = true; RunDelegate r = new RunDelegate(hae.UpdateNumber); AsyncCallback ac = new AsyncCallback(UpdateDone); IAsyncResult ar = r.BeginInvoke(Input, ac, null); } public void Stop() { running = false; } public void UpdateDone(IAsyncResult ar) { RunDelegate r = (RunDelegate)((AsyncResult)ar).AsyncDelegate; r.EndInvoke(ar); if (running) { AsyncCallback ac = new AsyncCallback(UpdateDone); IAsyncResult ar2 = r.BeginInvoke(Input, ac, null); } } HasAnEvent has a function that generates the sin of its input and fires an event with that result as its argument. i.e.: public void UpdateNumber(double val) { AnEventArgs e = new AnEventArgs(Math.Sin(val)); System.Threading.Thread.Sleep(1000); if (null != AnEvent) { AnEvent(e); } } The sleep is in there just to slow things down a bit. The problem I am getting is that the algorithm is not coming up with the best input being PI/2 and the final input being PI, but I can't see why. Also the best and final inputs are different each time I run the programme. Can anyone see why? Also when the algorithm terminates the best and final inputs are printed to the screen multiple times, not just once. Can someone explain why?

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  • Ruby on rails model and controllers inside of different namespaces

    - by Nelson LaQuet
    OK. This is insane. I'm new to RoR and I really want to get into it as everything about it that I have seen so far makes it more appealing to the type of work that I do. However, I can't seem to accomplish a very simple thing with RoR. I want these controlers: /admin/blog/entries (index/show/edit/delete) /admin/blog/categories (index/show/edit/delete) /admin/blog/comments (index/show/edit/delete) ... and so on And these models: Blog::Entry (table: blog_entries) Blog::Category (table: blog_categories) Blog::Comments (table: blog_comments) ... and so on Now, I have already gone though quite a bit of misery to make this work. My first attempt was with generating scaffolding (I'm using 2.2.2). I generated my scaffolding, but had to move my model, then fix the references to the model in my controller (see http://stackoverflow.com/questions/903258/ruby-on-rails-model-inside-namespace-cant-be-found-in-controller). That is already a big of a pain, but hey, I got it to work. Now though form_for won't work and I cannot figure out how to use the url helpers (I have no idea what these are called... they are the automatically generated methods that return URLs to controllers associated with a model). I cannot figure out what their name is. My model is Blog::Entries. I have tried to mess with the route.rb's map's resource method, but no luck. When I attempt to use form_for with my model, I get this error undefined method `blog_entries_path' for #<ActionView::Base:0xb6848080> Now. This is really quite frustrating. I am not going to completely destroy my code's organization in order to use this framework, and if I cannot figure out how to accomplish this simple task (I have been researching this for at least 5 hours) then I simply cannot continue. Are there any ideas on how to accomplish this? Thanks EDIT Here are my routes: admin_blog_entries GET /admin_blog_entries {:controller=>"admin_blog_entries", :action=>"index"} formatted_admin_blog_entries GET /admin_blog_entries.:format {:controller=>"admin_blog_entries", :action=>"index"} POST /admin_blog_entries {:controller=>"admin_blog_entries", :action=>"create"} POST /admin_blog_entries.:format {:controller=>"admin_blog_entries", :action=>"create"} new_admin_blog_entry GET /admin_blog_entries/new {:controller=>"admin_blog_entries", :action=>"new"} formatted_new_admin_blog_entry GET /admin_blog_entries/new.:format {:controller=>"admin_blog_entries", :action=>"new"} edit_admin_blog_entry GET /admin_blog_entries/:id/edit {:controller=>"admin_blog_entries", :action=>"edit"} formatted_edit_admin_blog_entry GET /admin_blog_entries/:id/edit.:format {:controller=>"admin_blog_entries", :action=>"edit"} admin_blog_entry GET /admin_blog_entries/:id {:controller=>"admin_blog_entries", :action=>"show"} formatted_admin_blog_entry GET /admin_blog_entries/:id.:format {:controller=>"admin_blog_entries", :action=>"show"} PUT /admin_blog_entries/:id {:controller=>"admin_blog_entries", :action=>"update"} PUT /admin_blog_entries/:id.:format {:controller=>"admin_blog_entries", :action=>"update"} DELETE /admin_blog_entries/:id {:controller=>"admin_blog_entries", :action=>"destroy"} DELE

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  • How to find the insertion point in an array using binary search?

    - by ????
    The basic idea of binary search in an array is simple, but it might return an "approximate" index if the search fails to find the exact item. (we might sometimes get back an index for which the value is larger or smaller than the searched value). For looking for the exact insertion point, it seems that after we got the approximate location, we might need to "scan" to left or right for the exact insertion location, so that, say, in Ruby, we can do arr.insert(exact_index, value) I have the following solution, but the handling for the part when begin_index >= end_index is a bit messy. I wonder if a more elegant solution can be used? (this solution doesn't care to scan for multiple matches if an exact match is found, so the index returned for an exact match may point to any index that correspond to the value... but I think if they are all integers, we can always search for a - 1 after we know an exact match is found, to find the left boundary, or search for a + 1 for the right boundary.) My solution: DEBUGGING = true def binary_search_helper(arr, a, begin_index, end_index) middle_index = (begin_index + end_index) / 2 puts "a = #{a}, arr[middle_index] = #{arr[middle_index]}, " + "begin_index = #{begin_index}, end_index = #{end_index}, " + "middle_index = #{middle_index}" if DEBUGGING if arr[middle_index] == a return middle_index elsif begin_index >= end_index index = [begin_index, end_index].min return index if a < arr[index] && index >= 0 #careful because -1 means end of array index = [begin_index, end_index].max return index if a < arr[index] && index >= 0 return index + 1 elsif a > arr[middle_index] return binary_search_helper(arr, a, middle_index + 1, end_index) else return binary_search_helper(arr, a, begin_index, middle_index - 1) end end # for [1,3,5,7,9], searching for 6 will return index for 7 for insertion # if exact match is found, then return that index def binary_search(arr, a) puts "\nSearching for #{a} in #{arr}" if DEBUGGING return 0 if arr.empty? result = binary_search_helper(arr, a, 0, arr.length - 1) puts "the result is #{result}, the index for value #{arr[result].inspect}" if DEBUGGING return result end arr = [1,3,5,7,9] b = 6 arr.insert(binary_search(arr, b), b) p arr arr = [1,3,5,7,9,11] b = 6 arr.insert(binary_search(arr, b), b) p arr arr = [1,3,5,7,9] b = 60 arr.insert(binary_search(arr, b), b) p arr arr = [1,3,5,7,9,11] b = 60 arr.insert(binary_search(arr, b), b) p arr arr = [1,3,5,7,9] b = -60 arr.insert(binary_search(arr, b), b) p arr arr = [1,3,5,7,9,11] b = -60 arr.insert(binary_search(arr, b), b) p arr arr = [1] b = -60 arr.insert(binary_search(arr, b), b) p arr arr = [1] b = 60 arr.insert(binary_search(arr, b), b) p arr arr = [] b = 60 arr.insert(binary_search(arr, b), b) p arr and result: Searching for 6 in [1, 3, 5, 7, 9] a = 6, arr[middle_index] = 5, begin_index = 0, end_index = 4, middle_index = 2 a = 6, arr[middle_index] = 7, begin_index = 3, end_index = 4, middle_index = 3 a = 6, arr[middle_index] = 5, begin_index = 3, end_index = 2, middle_index = 2 the result is 3, the index for value 7 [1, 3, 5, 6, 7, 9] Searching for 6 in [1, 3, 5, 7, 9, 11] a = 6, arr[middle_index] = 5, begin_index = 0, end_index = 5, middle_index = 2 a = 6, arr[middle_index] = 9, begin_index = 3, end_index = 5, middle_index = 4 a = 6, arr[middle_index] = 7, begin_index = 3, end_index = 3, middle_index = 3 the result is 3, the index for value 7 [1, 3, 5, 6, 7, 9, 11] Searching for 60 in [1, 3, 5, 7, 9] a = 60, arr[middle_index] = 5, begin_index = 0, end_index = 4, middle_index = 2 a = 60, arr[middle_index] = 7, begin_index = 3, end_index = 4, middle_index = 3 a = 60, arr[middle_index] = 9, begin_index = 4, end_index = 4, middle_index = 4 the result is 5, the index for value nil [1, 3, 5, 7, 9, 60] Searching for 60 in [1, 3, 5, 7, 9, 11] a = 60, arr[middle_index] = 5, begin_index = 0, end_index = 5, middle_index = 2 a = 60, arr[middle_index] = 9, begin_index = 3, end_index = 5, middle_index = 4 a = 60, arr[middle_index] = 11, begin_index = 5, end_index = 5, middle_index = 5 the result is 6, the index for value nil [1, 3, 5, 7, 9, 11, 60] Searching for -60 in [1, 3, 5, 7, 9] a = -60, arr[middle_index] = 5, begin_index = 0, end_index = 4, middle_index = 2 a = -60, arr[middle_index] = 1, begin_index = 0, end_index = 1, middle_index = 0 a = -60, arr[middle_index] = 9, begin_index = 0, end_index = -1, middle_index = -1 the result is 0, the index for value 1 [-60, 1, 3, 5, 7, 9] Searching for -60 in [1, 3, 5, 7, 9, 11] a = -60, arr[middle_index] = 5, begin_index = 0, end_index = 5, middle_index = 2 a = -60, arr[middle_index] = 1, begin_index = 0, end_index = 1, middle_index = 0 a = -60, arr[middle_index] = 11, begin_index = 0, end_index = -1, middle_index = -1 the result is 0, the index for value 1 [-60, 1, 3, 5, 7, 9, 11] Searching for -60 in [1] a = -60, arr[middle_index] = 1, begin_index = 0, end_index = 0, middle_index = 0 the result is 0, the index for value 1 [-60, 1] Searching for 60 in [1] a = 60, arr[middle_index] = 1, begin_index = 0, end_index = 0, middle_index = 0 the result is 1, the index for value nil [1, 60] Searching for 60 in [] [60]

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  • Template problems: No matching function for call

    - by Nick Sweet
    I'm trying to create a template class, and when I define a non-member template function, I get the "No matching function for call to randvec()" error. I have a template class defined as: template <class T> class Vector { T x, y, z; public: //constructors Vector(); Vector(const T& x, const T& y, const T& z); Vector(const Vector& u); //accessors T getx() const; T gety() const; T getz() const; //mutators void setx(const T& x); void sety(const T& y); void setz(const T& z); //operations void operator-(); Vector plus(const Vector& v); Vector minus(const Vector& v); Vector cross(const Vector& v); T dot(const Vector& v); void times(const T& s); T length() const; //Vector<T>& randvec(); //operators Vector& operator=(const Vector& rhs); friend std::ostream& operator<< <T>(std::ostream&, const Vector<T>&); }; and the function in question, which I've defined after all those functions above, is: //random Vector template <class T> Vector<double>& randvec() { const int min=-10, max=10; Vector<double>* r = new Vector<double>; int randx, randy, randz, temp; const int bucket_size = RAND_MAX/(max-min +1); temp = rand(); //voodoo hackery do randx = (rand()/bucket_size)+min; while (randx < min || randx > max); r->setx(randx); do randy = (rand()/bucket_size)+min; while (randy < min || randy > max); r->sety(randy); do randz = (rand()/bucket_size)+min; while (randz < min || randz > max); r->setz(randz); return *r; } Yet, every time I call it in my main function using a line like: Vector<double> a(randvec()); I get that error. However, if I remove the template and define it using 'double' instead of 'T', the call to randvec() works perfectly. Why doesn't it recognize randvec()? P.S. Don't mind the bit labeled voodoo hackery - this is just a cheap hack so that I can get around another problem I encountered.

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  • How do I get confidence intervals without inverting a singular Hessian matrix?

    - by AmalieNot
    Hello. I recently posted this to reddit and it was suggested I come here, so here I am. I'm a student working on an epidemiology model in R, using maximum likelihood methods. I created my negative log likelihood function. It's sort of gross looking, but here it is: NLLdiff = function(v1, CV1, v2, CV2, st1 = (czI01 - czV01), st2 = (czI02 - czV02), st01 = czI01, st02 = czI02, tt1 = czT01, tt2 = czT02) { prob1 = (1 + v1 * CV1 * tt1)^(-1/CV1) prob2 = ( 1 + v2 * CV2 * tt2)^(-1/CV2) -(sum(dbinom(st1, st01, prob1, log = T)) + sum(dbinom(st2, st02, prob2, log = T))) } The reason the first line looks so awful is because most of the data it takes is inputted there. czI01, for example, is already declared. I did this simply so that my later calls to the function don't all have to have awful vectors in them. I then optimized for CV1, CV2, v1 and v2 using mle2 (library bbmle). That's also a bit gross looking, and looks like: ml.cz.diff = mle2 (NLLdiff, start=list(v1 = vguess, CV1 = cguess, v2 = vguess, CV2 = cguess), method="L-BFGS-B", lower = 0.0001) Now, everything works fine up until here. ml.cz.diff gives me values that I can turn into a plot that reasonably fits my data. I also have several different models, and can get AICc values to compare them. However, when I try to get confidence intervals around v1, CV1, v2 and CV2 I have problems. Basically, I get a negative bound on CV1, which is impossible as it actually represents a square number in the biological model as well as some warnings. The warnings are this: http://i.imgur.com/B3H2l.png . Is there a better way to get confidence intervals? Or, really, a way to get confidence intervals that make sense here? What I see happening is that, by coincidence, my hessian matrix is singular for some values in the optimization space. But, since I'm optimizing over 4 variables and don't have overly extensive programming knowledge, I can't come up with a good method of optimization that doesn't rely on the hessian. I have googled the problem - it suggested that my model's bad, but I'm reconstructing some work done before which suggests that my model's really not awful (the plots I make using the ml.cz.diff look like the plots of the original work). I have also read the relevant parts of the manual as well as Bolker's book Ecological Models in R. I have also tried different optimization methods, which resulted in a longer run time but the same errors. The "SANN" method didn't finish running within an hour, so I didn't wait around to see the result. tl;dr : my confidence intervals are bad, is there a relatively straightforward way to fix them in R. My vectors are: czT01 = c(5, 5, 5, 5, 5, 5, 5, 25, 25, 25, 25, 25, 25, 25, 50, 50, 50, 50, 50, 50, 50) czT02 = c(5, 5, 5, 5, 5, 10, 10, 10, 10, 10, 25, 25, 25, 25, 25, 50, 50, 50, 50, 50, 75, 75, 75, 75, 75) czI01 = c(25, 24, 22, 22, 26, 23, 25, 25, 25, 23, 25, 18, 21, 24, 22, 23, 25, 23, 25, 25, 25) czI02 = c(13, 16, 5, 18, 16, 13, 17, 22, 13, 15, 15, 22, 12, 12, 13, 13, 11, 19, 21, 13, 21, 18, 16, 15, 11) czV01 = c(1, 4, 5, 5, 2, 3, 4, 11, 8, 1, 11, 12, 10, 16, 5, 15, 18, 12, 23, 13, 22) czV02 = c(0, 3, 1, 5, 1, 6, 3, 4, 7, 12, 2, 8, 8, 5, 3, 6, 4, 6, 11, 5, 11, 1, 13, 9, 7) and I get my guesses by: v = -log((c(czI01, czI02) - c(czV01, czV02))/c(czI01, czI02))/c(czT01, czT02) vguess = mean(v) cguess = var(v)/vguess^2 It's also possible that I'm doing something else completely wrong, but my results seem reasonable so I haven't caught it.

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  • What's the most unsound program you've had to maintain?

    - by Robert Rossney
    I periodically am called upon to do maintenance work on a system that was built by a real rocket surgeon. There's so much wrong with it that it's hard to know where to start. No, wait, I'll start at the beginning: in the early days of the project, the designer was told that the system would need to scale, and he'd read that a source of scalability problems was traffic between the application and database servers, so he made sure to minimize this traffic. How? By putting all of the application logic in SQL Server stored procedures. Seriously. The great bulk of the application functions by the HTML front end formulating XML messages. When the middle tier receives an XML message, it uses the document element's tag name as the name of the stored procedure it should call, and calls the SP, passing it the entire XML message as a parameter. It takes the XML message that the SP returns and returns it directly back to the front end. There is no other logic in the application tier. (There was some code in the middle tier to validate the incoming XML messages against a library of schemas. But I removed it, after ascertaining that 1) only a small handful of messages had corresponding schemas, 2) the messages didn't actually conform to these schemas, and 3) after validating the messages, if any errors were encountered, the method discarded them. "This fuse box is a real time-saver - it comes from the factory with pennies pre-installed!") I've seen software that does the wrong thing before. Lots of it. I've written quite a bit. But I've never seen anything like the steely-eyed determination to do the wrong thing, at every possible turn, that's embodied in the design and programming of this system. Well, at least he went with what he knew, right? Um. Apparently, what he knew was Access. And he didn't really understand Access. Or databases. Here's a common pattern in this code: SELECT @TestCodeID FROM TestCode WHERE TestCode = @TestCode SELECT @CountryID FROM Country WHERE CountryAbbr = @CountryAbbr SELECT Invoice.*, TestCode.*, Country.* FROM Invoice JOIN TestCode ON Invoice.TestCodeID = TestCode.ID JOIN Country ON Invoice.CountryID = Country.ID WHERE Invoice.TestCodeID = @TestCodeID AND Invoice.CountryID = @CountryID Okay, fine. You don't trust the query optimizer either. But how about this? (Originally, I was going to post this in What's the best comment in source code you have ever encountered? but I realized that there was so much more to write about than just this one comment, and things just got out of hand.) At the end of many of the utility stored procedures, you'll see code that looks like the following: -- Fix NULLs SET @TargetValue = ISNULL(@TargetValue, -9999) Yes, that code is doing exactly what you can't allow yourself to believe it's doing lest you be driven mad. If the variable contains a NULL, he's alerting the caller by changing its value to -9999. Here's how this number is commonly used: -- Get target value EXEC ap_GetTargetValue @Param1, @Param2, OUTPUT @TargetValue -- Check target value for NULL value IF @TargetValue = -9999 ... Really. For another dimension of this system, see the article on thedailywtf.com entitled I Think I'll Call Them "Transactions". I'm not making any of this up. I swear. I'm often reminded, when I work on this system, of Wolfgang Pauli's famous response to a student: "That isn't right. It isn't even wrong." This can't really be the very worst program ever. It's definitely the worst one I've worked

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  • Intrinsics program (SSE) - g++ - help needed

    - by Sriram
    Hi all, This is the first time I am posting a question on stackoverflow, so please try and overlook any errors I may have made in formatting my question/code. But please do point the same out to me so I may be more careful. I was trying to write some simple intrinsics routines for the addition of two 128-bit (containing 4 float variables) numbers. I found some code on the net and was trying to get it to run on my system. The code is as follows: //this is a sample Intrinsics program to add two vectors. #include <iostream> #include <iomanip> #include <xmmintrin.h> #include <stdio.h> using namespace std; struct vector4 { float x, y, z, w; }; //functions to operate on them. vector4 set_vector(float x, float y, float z, float w = 0) { vector4 temp; temp.x = x; temp.y = y; temp.z = z; temp.w = w; return temp; } void print_vector(const vector4& v) { cout << " This is the contents of vector: " << endl; cout << " > vector.x = " << v.x << endl; cout << " vector.y = " << v.y << endl; cout << " vector.z = " << v.z << endl; cout << " vector.w = " << v.w << endl; } vector4 sse_vector4_add(const vector4&a, const vector4& b) { vector4 result; asm volatile ( "movl $a, %eax" //move operands into registers. "\n\tmovl $b, %ebx" "\n\tmovups (%eax), xmm0" //move register contents into SSE registers. "\n\tmovups (%ebx), xmm1" "\n\taddps xmm0, xmm1" //add the elements. addps operates on single-precision vectors. "\n\t movups xmm0, result" //move result into vector4 type data. ); return result; } int main() { vector4 a, b, result; a = set_vector(1.1, 2.1, 3.2, 4.5); b = set_vector(2.2, 4.2, 5.6); result = sse_vector4_add(a, b); print_vector(a); print_vector(b); print_vector(result); return 0; } The g++ parameters I use are: g++ -Wall -pedantic -g -march=i386 -msse intrinsics_SSE_example.C -o h The errors I get are as follows: intrinsics_SSE_example.C: Assembler messages: intrinsics_SSE_example.C:45: Error: too many memory references for movups intrinsics_SSE_example.C:46: Error: too many memory references for movups intrinsics_SSE_example.C:47: Error: too many memory references for addps intrinsics_SSE_example.C:48: Error: too many memory references for movups I have spent a lot of time on trying to debug these errors, googled them and so on. I am a complete noob to Intrinsics and so may have overlooked some important things. Any help is appreciated, Thanks, Sriram.

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  • Javascript Closures - What are the negatives?

    - by vol7ron
    Question: There seem to be many benefits to Closures, but what are the negatives (memory leakage? obfuscation problems? bandwidth increasage?)? Additionally, is my understanding of Closures correct? Finally, once closures are created, can they be destroyed? I've been reading a little bit about Javascript Closures. I hope someone a little more knowledgeable will guide my assertions, correcting me where wrong. Benefits of Closures: Encapsulate the variables to a local scope, by using an internal function. The anonymity of the function is insignificant. What I've found helpful is to do some basic testing, regarding local/global scope: <script type="text/javascript"> var global_text = ""; var global_count = 0; var global_num1 = 10; var global_num2 = 20; var global_num3 = 30; function outerFunc() { var local_count = local_count || 0; alert("global_num1: " + global_num1); // global_num1: undefined var global_num1 = global_num1 || 0; alert("global_num1: " + global_num1); // global_num1: 0 alert("global_num2: " + global_num2); // global_num2: 20 global_num2 = global_num2 || 0; // (notice) no definition with 'var' alert("global_num2: " + global_num2); // global_num2: 20 global_num2 = 0; alert("local_count: " + local_count); // local_count: 0 function output() { global_num3++; alert("local_count: " + local_count + "\n" + "global_count: " + global_count + "\n" + "global_text: " + global_text ); local_count++; } local_count++; global_count++; return output; } var myFunc = outerFunc(); myFunc(); /* Outputs: ********************** * local_count: 1 * global_count: 1 * global_text: **********************/ global_text = "global"; myFunc(); /* Outputs: ********************** * local_count: 2 * global_count: 1 * global_text: global **********************/ var local_count = 100; myFunc(); /* Outputs: ********************** * local_count: 3 * global_count: 1 * global_text: global **********************/ alert("global_num1: " + global_num1); // global_num1: 10 alert("global_num2: " + global_num2); // global_num2: 0 alert("global_num3: " + global_num3); // global_num3: 33 </script> Interesting things I took out of it: The alerts in outerFunc are only called once, which is when the outerFunc call is assigned to myFunc (myFunc = outerFunc()). This assignment seems to keep the outerFunc open, in what I would like to call a persistent state. Everytime myFunc is called, the return is executed. In this case, the return is the internal function. Something really interesting is the localization that occurs when defining local variables. Notice the difference in the first alert between global_num1 and global_num2, even before the variable is trying to be created, global_num1 is considered undefined because the 'var' was used to signify a local variable to that function. -- This has been talked about before, in the order of operation for the Javascript engine, it's just nice to see this put to work. Globals can still be used, but local variables will override them. Notice before the third myFunc call, a global variable called local_count is created, but it as no effect on the internal function, which has a variable that goes by the same name. Conversely, each function call has the ability to modify global variables, as noticed by global_var3. Post Thoughts: Even though the code is straightforward, it is cluttered by alerts for you guys, so you can plug and play. I know there are other examples of closures, many of which use anonymous functions in combination with looping structures, but I think this is good for a 101-starter course to see the effects. The one thing I'm concerned with is the negative impact closures will have on memory. Because it keeps the function environment open, it is also keeping those variables stored in memory, which may/may not have performance implications, especially regarding DOM traversals and garbage collection. I'm also not sure what kind of role this will play in terms of memory leakage and I'm not sure if the closure can be removed from memory by a simple "delete myFunc;." Hope this helps someone, vol7ron

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